proposal: give delattr ability to ignore missing attribute

[Gary Wilson]

I would like to propose that functionality be added to delattr to
handle the case when the attribute does not exist.

First off, getattr handles this nicely with the default parameter:

value = getattr(obj, 'foo', False)

instead of:

try:
value = getattr(obj, 'foo')
except AttributeError:
value = False

or:

if hasattr(obj, 'foo'):
value = getattr(obj, 'foo')
else:
value = False


And I think it makes sense to have something similar for delattr (name
the argument as you wish):

delattr(obj, 'foo', allow_missing=True)

instead of:

try:
delattr(obj, 'foo')
except AttributeError:
pass

or:

try:
del obj.foo
except AttributeError:
pass

or:

if hasattr(obj, 'foo')
delattr(obj, 'foo')

For backwards compatibility, allow_missing would default to False.

Gary

 

[Lie]

I would like to propose that functionality be added to delattr to
handle the case when the attribute does not exist.

First off, getattr handles this nicely with the default parameter:

value = getattr(obj, 'foo', False)

instead of:

try:
    value = getattr(obj, 'foo')
except AttributeError:
    value = False

or:

if hasattr(obj, 'foo'):
    value = getattr(obj, 'foo')
else:
    value = False

And I think it makes sense to have something similar for delattr (name
the argument as you wish):

delattr(obj, 'foo', allow_missing=True)

instead of:

try:
    delattr(obj, 'foo')
except AttributeError:
    pass

or:

try:
    del obj.foo
except AttributeError:
    pass

or:

if hasattr(obj, 'foo')
    delattr(obj, 'foo')

For backwards compatibility, allow_missing would default to False.

Gary

That doesn't need to be implemented internally, you could do it
yourself in python.

def my_delattr(obj, attr):
try:
delattr(obj, attr)
except AttributeError:
pass
def my_getattr(obj, attr, default):
try:
return getattr(obj, attr)
except AttributeError:
return default

 

[Fuzzyman]

I've never once needed that functionality. In fact I very rarely use
delattr at all. I don't think there is a compelling enough use case
for adding this to Python.

Michael Foord
http://www.ironpythoninaction.com/